JP3475200B2 - Decorated styrenic resin molded product - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a decorated styrene resin molded product obtained by transferring a pattern or the like to a styrene resin molded product by using a decorative transfer foil.

[0002]

2. Description of the Related Art A method of transferring a design or the like to a styrene resin molded product using a decorative transfer foil has been known in the past, and the hot stamping method is widely used.
However, the hot stamping method is likely to cause cracks on the transfer surface due to distortion caused during molding of resin or thermal transfer and permeation of oil components such as hand oil, and the styrene-acrylonitrile copolymer resin is expensive as a styrene resin. Was commonly used.

Further, Japanese Patent Application Laid-Open No. 62-259883 discloses a technique in which a pattern is transferred to a molded product of a styrene resin and then annealed, that is, a process of removing distortion by heating is performed. The styrene-based resin used in the above is a so-called impact-resistant polystyrene-based resin, which is expensive and opaque as the styrene-based resin.

[0004]

On the other hand, in order to transfer a pattern to an inexpensive styrene-based resin molded product made of a general polystyrene-based resin and having excellent transparency, the styrene-based resin molded product is hot. Before or after stamping,
Furthermore, there is a problem that a special treatment such as annealing treatment is required both before and after, which does not necessarily lead to cost reduction.

As a result of various investigations to solve the above problems, the inventors of the present invention decorate a pattern or the like by a hot stamping method by using a molded product of a specific styrene-based resin to bring oils and fats into contact with the transfer surface. Even if there is a possibility, it is a completed styrenic resin molded product with good hot stamping properties (performance to withstand the phenomenon of cracking on the hot stamping surface) without annealing. .

Furthermore, since a cheap styrene resin molded product is used and no special treatment such as annealing is required, problems such as cost reduction can be solved.

[0007]

[Means for Solving the Problems] That is, the present invention relates to a styrene-based polymer having at least one styrene-based monomer selected from styrene, α-substituted alkylstyrene and nucleus-substituted alkylstyrene as a monomer unit. Styrene series containing 100 to 92 parts by weight of the coalesce and 0 to 8 parts by weight of a plasticizer and / or a lubricant, and having a relative viscosity of a 0.01 g / ml toluene solution at 30 ° C. of 2.2 to 3.5. A transfer layer having a design layer is formed on the resin molded product by the hot stamping method.
The present invention relates to a decorated styrene resin molded article characterized by being transferred by

The present invention will be described in detail below. The decorated styrene resin molded product of the present invention is composed of a styrene resin molded product and a transfer layer having a pattern layer.

The molded product of styrene resin in the present invention is a molded product of styrene resin comprising a styrene polymer and a plasticizer and / or a lubricant. The styrene polymer preferably has a polyfunctional vinyl monomer unit. Styrene-based polymers include styrene, α-methylstyrene, α
-Α-, such as ethylstyrene and α-isopropylstyrene
It can be obtained by polymerizing a styrene-based monomer such as a substituted alkylstyrene, p-methylstyrene, m-methylstyrene, or a nucleus-substituted alkylstyrene such as 2,5-dimethylstyrene.

Styrene-based polymers having a preferred polyfunctional vinyl monomer unit include the above-mentioned styrene-based monomers such as non-conjugated divinyl monomers such as divinylbenzene, polyethylene glycol diacrylate and polypropylene glycol dimethacrylate. It is obtained by adding and copolymerizing a polyfunctional vinyl monomer such as a polyvalent acrylate monomer.

The polyfunctional vinyl monomer copolymerized with the styrene-based polymer is 200 × 1 with respect to the styrene-based polymer.
^0-4 % by weight or less, preferably 3 x 10 ^{-4 to} 100 x 10
^-4 wt% is desirable. When the polyfunctional vinyl monomer unit is copolymerized, the oil resistance of the styrenic polymer is improved and the hot stamping property is improved, but the polyfunctional vinyl monomer unit is 200 × 10 ⁻ with respect to the styrene polymer. ^{If the} copolymerization exceeds ⁴ % by weight, molding defects such as flow marks and silver will occur during molding, resulting in poor appearance of the molded product.

Further, in the present invention, when a styrenic polymer is obtained, acrylonitrile, methyl methacrylate, methacrylic acid, maleic anhydride,
Monomers other than styrene-based monomers such as cyclohexylmaleimide and phenylmaleimide can also be used if they are 10% by weight or less based on the styrene-based polymer. Further, the styrene polymer can be obtained by a known method such as bulk polymerization, solution polymerization, suspension polymerization, emulsion polymerization.

As the plasticizer used in the present invention, those which are generally used can be used without particular limitation. Examples thereof include phthalate esters such as dioctyl phthalate and dibutyl phthalate, and tricresyl phosphate. Examples thereof include phosphoric acid ester.

As the lubricant, those which are generally used can be used without particular limitation.
For example, hydrocarbon compounds such as liquid paraffin and natural paraffin, higher fatty acids such as stearic acid and behenic acid and metal salts thereof, stearylamide, fatty acid amides such as ethylenebisstearylamide, stearyl alcohol, aliphatic alcohols such as ethylene glycol, Examples thereof include glyceride.

The mixing method of the styrene polymer and the plasticizer and / or the lubricant is not particularly limited, but for example, a method of adding the plasticizer and / or the lubricant during the polymerization of the styrene polymer, an extruder or the like may be used. It can be performed by a method such as melt kneading.

The ratio of the styrene-based polymer to the plasticizer and / or the lubricant in the styrene-based resin is 92
To 100 parts by weight, preferably 94 to 99 parts by weight, and 0 to 8 parts by weight, preferably 1 to 6 parts by weight of the plasticizer and / or the lubricant. By containing the plasticizer and / or the lubricant, the strain during molding of the styrene resin is reduced and the hot stamping property of the molded product is improved, but the plasticizer and / or the lubricant is 8% by weight based on the styrene resin. If it is contained in excess, the mold will be contaminated during molding and the appearance of the molded product will be impaired.
Moreover, the ratio of the plasticizer to the lubricant is not particularly limited.

The styrene resin used in the present invention has a relative viscosity of a 0.01 g / ml toluene solution at 30 ° C. of 2.2 to 3.5, preferably 2.25 to 3.3. If the relative viscosity is less than 2.2, the hot stamping property will be inferior such as cracks occurring after the hot stamping process, and if it exceeds 3.5, the productivity at the time of polymerization will be very poor and the hot stamping property will be improved. It will be less effective.

The relative viscosity is 0.01 g / m in a capillary tube at 30 ° C. using an Ubbelohde viscometer.
It is a value determined from the following formula 1 by measuring the time (t and t _0, respectively) during which the toluene solution of 1 and the toluene solvent flow down.

[0019]

[Equation 1]

The styrenic resin molded article in the present invention is a styrenic resin molded article by a known molding method such as injection molding or vacuum molding. The temperature at the time of molding is not particularly limited, but molding strain is likely to occur when molding is performed at a low temperature, and decomposition products are generated when molding at a high temperature. Therefore, it is preferably performed at 160 ° C to 280 ° C.

The decorated styrene resin molded article of the present invention is obtained by decorating a styrene resin molded article with a transfer layer having a pattern layer. The transfer layer having a pattern layer can be obtained by, for example, transferring a known decorative transfer foil to a molded product of styrene resin, but from the viewpoint of preventing oil from penetrating from the transfer surface, it is a decorative layer having oil resistance. It is preferable to use a transfer foil.

An example of the decorative transfer foil will be described with reference to the drawings. FIG. 1 is a cross-sectional view of a general decorative transfer foil in which a release layer 2, a pattern layer 3, and an adhesive layer 4 are formed on a base sheet 1. FIG. 2 is a cross-sectional view of a decorative transfer foil having oil resistance in which a release layer 2, an oil resistant layer 5, a pattern layer 3, and an adhesive layer 4 are formed on a base sheet 1. FIG. 3 is a sectional view of a decorative transfer foil having oil resistance in which an oil resistant layer 5, a pattern layer 3 and an adhesive layer 4 are formed on a base sheet 1. FIG. 4 is a decorative transfer foil having oil resistance in which a release layer 2, an oil resistant layer 5, a colored layer 8, a front anchor layer 6, a metal thin film layer 9, a rear anchor layer 7 and an adhesive layer 4 are formed on a base sheet 1. FIG.

As the base sheet 1, a plastic film or paper such as polyethylene terephthalate, polypropylene, polyethylene, nylon, cellophane, etc., or a composite film of these is usually used, and the release treatment is carried out by coating with a melamine resin or the like. May be applied.

The peeling layer 2 is a layer which is peeled off from the base sheet 1 at the time of transfer and becomes a surface of a styrene resin molded product. As the release layer, acrylic resin, vinyl resin, thermoplastic resin such as cellulose resin, or urethane resin,
A two-part curable resin such as an epoxy resin may be used.

The oil resistant layer 5 is a layer for preventing oil permeation. A curable resin such as an acrylic resin, a polyurethane resin, a urethane acrylate resin, a melamine resin, or an epoxy resin may be used as the oil resistant layer 5. As means for curing these curable resins, there are methods such as heating, ultraviolet ray irradiation, and electron beam irradiation. Further, the oil resistant layer may have peelability. When using an oil-resistant layer having peelability, the peeling layer may not be provided. Examples of the oil-repellent layer having releasability include those made of an ultraviolet curable resin or an electron beam curable resin.

The pattern layer 3 is formed on the release layer 2 or the oil resistant layer 5 or the like. As the pattern layer 3, an ordinary pigment or dye, and a coloring ink composed of a binder, an additive, etc. are used,
It is formed by an ordinary printing method such as a gravure printing method or a screen printing method. As the coloring ink, it is preferable to use one having excellent adhesion to the release layer and excellent weather resistance. The design layer may be a single layer or a multi-layered structure having multiple colors.
Further, the pattern layer may be a metal thin film layer 9 of aluminum, nickel or the like formed by a vacuum deposition method, a sputtering method, an ion plating method or the like in order to express a metallic luster. Further, the pattern layer may be a combination of the colored layer 8 made of colored ink and the metal thin film layer 9. The metal thin film layer may be provided entirely or partially. Further, when the metal thin film layer is provided, the front anchor layer 6 and the rear anchor layer 7 may be provided in order to improve the adhesion of the metal thin film layer.

The adhesive layer 4 is for adhering each of the above layers to a styrene resin molded product. The adhesive layer may be formed entirely on the pattern layer 3 and the release layer 2. As the adhesive layer, a heat-sensitive or pressure-sensitive resin suitable for a styrene resin is appropriately used. For example, a thermoplastic resin such as an acrylic resin can be used. Further, a pigment may be added to prevent burrs from occurring.

The transfer layer 10 is obtained by peeling the base sheet 1 from the above decorative transfer foil. It should be noted that the above-mentioned structure shows an example of the decorative transfer foil of the present invention, and the present invention is not limited to this. For example, when a white layer is required on the back side of the entire pattern layer for the purpose of hiding, the adhesive layer may be white.

As a method of transferring the decorative transfer foil onto the molded product of the styrene resin by using the decorative transfer foil thus constructed, a known hot stamp such as a roll transfer method or an up-down transfer method is used. You can use the law.

Here, an example of a transfer method of the decorative transfer foil will be described with reference to the drawings. FIG. 5 is an explanatory view showing the steps of the method for roll-transferring the decorative transfer foil. The adhesive layer of the decorative transfer foil 11 is brought into close contact with the molded product 13 of styrene resin, and the heating member 12 heats and presses it from above the base sheet of the decorative transfer foil 11. As the heating member 12, for example, an elastic body such as silicon rubber can be used. next,
When the base sheet of the decorative transfer foil 11 is peeled off, peeling occurs at the boundary surface between the base sheet and the peeling layer. In this way, the transfer step is completed, and the transfer layer having the design layer can be formed on the styrene resin molded product.

The transfer temperature is not particularly limited, but it is preferably performed at 160 ° C to 240 ° C.

[0032]

The function of the decorated styrene resin molded article of the present invention is as follows:
A styrenic polymer having a polyfunctional vinyl monomer unit,
Since a transfer layer having a pattern layer is formed on a molded product of a plasticizer and / or a lubricant, and a styrene resin whose relative viscosity is within a specific range, distortion generated during molding or thermal transfer is prevented. Since the number is small and the oil resistance is excellent, cracks on the transfer surface due to oil permeation are unlikely to occur, and the hot stamping property is good even without annealing treatment.

As the transfer layer having the pattern layer of the decorated styrenic resin molded article of the present invention, both general oil-resistant ones and oil-resistant ones can be used, but particularly oil resistance When a transfer layer having a pattern layer having a is used, oil permeation adhered to the surface of the transfer layer having a pattern layer is blocked as compared with the case where a transfer layer having a general pattern layer having no oil resistance is used. The hot stamping property becomes better.

[0034]

EXAMPLES The present invention will be described below with reference to examples.
The invention is not limited by these examples.

Reference Example 1 On a 25 μm thick polyester film, a release layer having the following composition 1, a pattern layer made of an acrylic resin, and an adhesive layer made of an acrylic resin were sequentially laminated to form a decorative transfer foil (hereinafter referred to as a general foil). Completed).

Composition 1 Methyl methacrylate 100 parts by weight Polyethylene wax 5 parts by weight

Reference Example 2 On a 25 μm thick polyester film, a release layer made of the following composition 2, an oil resistant layer made of the composition 3 below, a pattern layer made of an acrylic resin, and an adhesive layer made of an acrylic resin were sequentially laminated to form a decorative transfer. A foil (hereinafter referred to as an oil resistant foil) was completed.

Composition 2 Methyl methacrylate 100 parts by weight Polyethylene wax 5 parts by weight Composition 3 Vinyl acetate resin 80 parts by weight Urethane resin 20 parts by weight Isocyanate (TDI) 15 parts by weight

Example 1 In an autoclave having a volume of 15 liters, 5 kg of pure water,
Sodium dodecylbenzenesulfonate (0.15 g) and tricalcium phosphate (20 g) were added, and the mixture was stirred at 300 rpm. Subsequently, 5 kg of styrene and 30 of liquid paraffin
0 g, divinylbenzene 0.25 g, and t-butyl peroxybenzoate 5 g were mixed in advance and charged into an autoclave. The autoclave was closed and polymerized at 110 ° C. for 6 hours and at 135 ° C. for 3 hours. Next, neutralization, dehydration, and drying were performed, and then extrusion was performed to form pellets.

This was injection-molded at a molding temperature of 200 ° C. and 230 ° C. to obtain a length of 65 mm × width of 90 mm × thickness of 1.3.
A molded product of mm was obtained. The general foil obtained in Reference Example 1 was transferred to the molded product by a silicone roll having a surface temperature of 220 ° C. at a load of 100 kg and a speed of 10 cm / sec to obtain a decorated styrene resin molded product. The results of measuring various physical properties are shown in Table 1.

Example 2 A styrenic resin molded article decorated by the same method as in Example 1 was obtained except that the polymerization was carried out without adding the divinylbenzene of Example 1. The results of measuring various physical properties are shown in Table 1.

Example 3 A styrenic resin molded article decorated in the same manner as in Example 1 was obtained except that 0.25 g of divinylbenzene of Example 1 was used and 0.75 g was used for the polymerization. The results of measuring various physical properties are shown in Table 1.

Example 4 A styrenic resin molded article decorated by the same method as in Example 1 was obtained except that the polymerization was carried out without adding the liquid paraffin of Example 1. The results of measuring various physical properties are shown in Table 1.

Example 5 A styrenic resin molded article decorated by the same method as in Example 1 was obtained except that the general foil was not used and the oil resistant foil obtained in Reference Example 2 was used. Table 1 shows the results of measuring various physical properties.
Shown in.

Example 6 A styrenic resin molded article decorated by the same method as in Example 2 was obtained except that the general foil was not used and the oil resistant foil was used.
The results of measuring various physical properties are shown in Table 1.

Example 7 A styrenic resin molded article decorated by the same method as in Example 1 was obtained except that 300 g of dibutyl phthalate was added instead of the liquid paraffin of Example 1 and polymerization was carried out. The results of measuring various physical properties are shown in Table 1.

Example 8 A styrenic resin molded article decorated in the same manner as in Example 1 except that 300 g of liquid paraffin of Example 1 was added to 150 g and dibutyl phthalate was added in an amount of 150 g to carry out polymerization. It was The results of measuring various physical properties are shown in Table 1.

Comparative Example 1 A styrenic resin molded article decorated by the same method as in Example 1 was obtained except that 0.25 g of divinylbenzene of Example 1 was used as 1.25 g to carry out polymerization. The results of measuring various physical properties are shown in Table 2. From Table 2, it can be seen that the appearance and hot stamping property of the molded product are inferior.

Comparative Example 2 A styrenic resin molded article decorated by the same method as in Example 1 was obtained except that the polymerization was carried out with the liquid paraffin of Example 1 as 300 g of 600 g. The results of measuring various physical properties are shown in Table 2. From Table 2, it can be seen that the appearance and hot stamping property of the molded product are inferior.

Comparative Example 3 Styrene was added to 4-methyl-2,4-diphenylpentene-
A styrenic resin molded article decorated by the same method as in Example 1 was obtained except that 2.5 g of 1 was polymerized. The results of measuring various physical properties are shown in Table 2. From Table 2, it can be seen that the hot stamping property is inferior.

Comparative Example 4 Styrene was added to 4-methyl-2,4-diphenylpentene-
A styrenic resin molded article decorated with the same method as in Example 5 was obtained except that 2.5 g of 1 was mixed and polymerization was performed. The results of measuring various physical properties are shown in Table 2. From Table 2, it can be seen that the hot stamping property is inferior.

[0052]

[Table 1]

[0053]

[Table 2]

The plasticizer and / or the lubricant in Tables 1 and 2 are parts by weight based on 100 parts by weight of the styrene polymer.

The appearance and hot stamping properties of the molded product were evaluated by the following methods. (1) Appearance of molded product: The appearance of a molded product obtained by injection molding was visually judged according to the following criteria, and a product in which no defective molding phenomenon occurred was accepted. Good: Molding failure phenomenon does not occur. X: A defective molding phenomenon such as flow mark, silver, mold stain, etc. occurred.

(2) Hot stamping property: After 24 hours of transfer, lard oil was applied to the transfer surface, and the state of cracking after 24 hours was visually judged according to the following criteria. I passed. Furthermore, the crack generation state 3 weeks after the application of lard oil was visually judged and the superiority or inferiority was evaluated. Good: No cracks occurred 24 hours after applying lard oil. -A: No cracks occurred even 3 weeks after the application of lard oil. -B: Minute crazing occurred within 3 weeks after applying lard oil. -C ... Minute cracks occurred within 3 weeks after application of lard oil. △ ……… Cracks occurred within 24 hours after application of lard oil. ×: Cracks occurred before the test of applying lard oil.

From Table 1 and Table 2, Comparative Example 1 was prepared from Examples 1 to 1.
It can be seen that the appearance and hot stamping property of the molded product are inferior to those of No. 3. It can be seen that Comparative Example 2 is inferior in appearance and hot stamping property of the molded product as compared with Examples 1 and 4. It can be seen that Comparative Example 3 is inferior to Example 1 in hot stamping property. It can be seen that Comparative Example 4 is inferior to Example 5 in hot stamping property.

[0058]

As described above, the decorated styrenic resin molded article of the present invention has little distortion generated during molding or thermal transfer, is less likely to cause cracks on the transfer surface due to oil permeation, and is annealed. Even without it, the hot stamping property becomes good. Further, since an inexpensive polystyrene resin molded product can be used and no special treatment such as annealing is required, it is useful for cost reduction.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a general decorative transfer foil.

FIG. 2 is a cross-sectional view of a decorative transfer foil having oil resistance.

FIG. 3 is a cross-sectional view of another decorative transfer foil having oil resistance.

FIG. 4 is a cross-sectional view of another decorative transfer foil having oil resistance.

FIG. 5 is an explanatory diagram showing steps of a method for roll-transferring a decorative transfer foil.

[Explanation of symbols]

1 Base sheet 2 Release layer 3 pattern layers 4 Adhesive layer 5 Oil resistant layer 6 Front anchor layer 7 Rear anchor layer 8 colored layers 9 Metal thin film layer 10 Transfer layer 11 Transfer foil for decoration 12 Heating member 13 Styrene resin molded products

─────────────────────────────────────────────────── ─── Continuation of front page (56) References JP-A-6-31773 (JP, A) JP-A-4-113900 (JP, A) JP-A-4-77545 (JP, A) (58) Field (Int.Cl. ⁷ , DB name) B44C 1/165-1/17

Claims (4)

(57) [Claims] 1. At least one selected from styrene, α-substituted alkylstyrenes and nucleus-substituted alkylstyrenes.
100 to 92 parts by weight of a styrene-based polymer having a styrene-based monomer as a monomer unit, and a plasticizer and / or a lubricant 0 to
Containing 8 parts by weight, and the molded article of the styrene-based resin relative viscosity of 2.2 to 3.5 at 30 ° C. at a concentration 0.01 g / ml toluene solution, e a transfer layer having a pattern layer
A decorated styrene resin molded product characterized by being transferred by the stamp method . 2. A styrene-based polymer is a polymer obtained by polymerization in the presence of a polyfunctional vinyl monomer in an amount of 200 × 10 ⁻⁴ wt% or less based on the monomers constituting the polymer. The decorated styrenic resin molded article according to claim 1. 3. A styrene-based polymer containing 10% by weight or less of a monomer unit selected from acrylonitrile, methyl methacrylate, methacrylic acid, maleic anhydride, cyclohexylmaleimide and phenylmaleimide together with the styrene-based monomer. The decorated styrene resin molded article according to claim 1 or 2, which is a united body. 4. The decorated styrenic resin molded article according to claim 1, wherein the transfer layer having the pattern layer is a transfer layer having oil resistance.